The subject matter disclosed herein relates to turbomachine purging and more specifically to combustor purging.
A gas turbine engine combusts a mixture of compressed air and fuel within a combustion chamber of a turbine combustor to produce hot combustion gases, and then drives one or more turbines with the resulting hot combustion gases. Unfortunately, the hot combustion gases may accumulate in various passages and/or cavities of the combustor, which may cause undesirable wear to components of the combustor and may lead to combustion at undesired locations, also referred to as flame holding and/or flashback. Accordingly, a purge gas, such as cooling air, may be provided to these passages to remove the hot combustion gases or flammable fuel-air mixtures to reduce the occurrence of flashback and/or flame holding. However, even with purge flows, pressure fluctuations in the combustor may cause momentary or prolonged backflow of the combustion gases or fuel-air mixtures into the passages.